Electronic voice box apparatus

ABSTRACT

A compact, hand held multivibrator activated artificial larynx to provide artificial voices of improved naturalness and intelligibility for patients having laryngectomy operations. Said artificial voice box being provided with push to talk switch means for intermittent operation, requiring only one hand to operate and use and adapted to produce a range of adjustable tones for loud and more natural voice reproduction.

United States Patent [191 Webb [ ELECTRONIC VOICE BOX APPARATUS [75]Inventor: Howard A. Webb, Austin, Tex.

[73] Assignee: Mary E. Morris, Austin, Tex.;

a part interest [22 Filed: Aiii-ffi ff97 i [21] Appl. N0.: 135,155

[52] 11.8. C1. 179/1 AL, 3/1.3 [51] Int. Cl. ..A61f1/20, G101 1/10 [58]Field of Search 3/1.3, l, 1.1; 179/1 AL, 121 C, 114 A, 115 A; 272/14;128/1 R, 1 C

[56] References Cited UNITED STATES PATENTS 3,066,186 11/1962 Trammell179/1 AL 3,072,745 1/1963 Barney 3/1.3 X

FOREIGN PATENTS OR APPLICATIONS 619,129 3/1961 Italy 128/1 C PrimaryExaminer-Richard A. Gaudet Assistant Examiner-Ronald L. FrinksAttorney-Marion E. Shafer [5 7] ABSTRACT A compact, hand heldmultivibrator activated artificial larynx to provide artificial voicesof improved naturalness and intelligibility for patients havinglaryngectomy operations. Said artificial voice box being provided withpush to talk switch means for intermittent operation, requiring only onehand to operate and use and adapted to produce a range of adjustabletones for loud and more natural voice reproduction.

1 Claim, 6 Drawing Figures Patented 0 53-; a ts-Sheet l F/GZ /I LLLUILLLU "Wu 1 n I HOWARD A. WEBB INVENTOR.

ATTORNEY Patented Get. 16, 1973 2 Sheets-Sheet 2 FIG. 6

HOWARD A. WEBB INVENTOR. BYWM ATTORNEY ELECTRONIC VOICE BOX APPARATUSSUBJECT MATTER OF INVENTION This Invention relates to artificiallarynxes and more particularly relates to unitary hand held electronicvoice box apparatus.

BACKGROUND OF THE INVENTION In a variety of accidental injury and throatinfection cases including malignant laryngeal tumors it often becomesnecessary to perform a laryngectomy in which the larynx or voice box isremoved. In such circumstances the patient incurs a highly frustratingloss of .speech. Efforts to teach laryngectomy patients to speak byconventional esophageal speech techniques of swollowing air andattempting to belch it back in such a manner as to produce an audiblesound that can be modulated into near speech like words is both a slowand difficult substitute for speech and is produced with such apparentlabored effort that it is exhausting to both the speaker and thoseattempting to understand him.

Patients who have difficulty with esophagel speech techniques oftendespair of ever learning to speak again and suffer psycologicallyinduced depression that adds to the complication of an already difficultsituation. In order to provide a convenient and more quickly and moreeasily mastered means and technique of speaking, a variety of so calledvibrator sound sources, artificial voice boxes and electronic tonegenerators have been provided for injecting a steady tone into the mouthof a laryngectomy patient that can be modulated for speech purposes to aconsiderable extent by manipulation of the patients tongue and lips.These devices have permitted the patient to regain a measure of abilityto speak within a very short time and therefore provide substantialencouragement to the patient during the critical period but such deviceshave often tended to be somewhat awkward in handling, have usuallyproduced a substantially continuous tone once they were turned on sothat uninterupted tone between words interferes with intelligibility ofthe speech pattern and in addition the usually flat speech patternresulting from speaking with a single tone source produces adisconcertingly unnatural sound.

OBJECTS OF THE INVENTION It is therefore a primary object of thisInvention to provide a highly compact, portable and self containedelectronic voice box source of speech modulatable sound that can beconveniently held and manipulated in one hand in such manner as to leavethe other hand free for writing, holding a telephone or performing 7other tasks.

Another object of the Invention is to provide improved artificial voicebox apparatus provided with a conveniently positioned push to talkswitch means for intermittent operation thereby allowing the patient toconveniently. interrupt the sound source during pauses in the speechpattern and during periods when other people are speaking. A furtherobject of this Invention is to produce an artificial voice source forsuch laryngectomy patients that can provide substantially increasedvolume or loudness and that is better suited to produce the frequencyand character of sounds that may be transmitted intelligibly over thetelephone.

A still further object of the Invention is to provide compactmultivibrator electronic means of activating an improved soundtransducer capable of producing a complex waveform rich in harmonics toprovide a more audible and more natural sound for the person using thedevice.

These and other objects and advantages of this Invention will becomeapparent through consideration of the following description and appendedclaims in conjunction with the attached drawings in which:

DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a perspectiveview of a person holding the device contemplated by this Invention inproper position for use with his thumb in position to activate the pushto talk button on said electronic artificial voice box.

FIG. 2 is a section plan view from one side of the Inventionillustrating arrangement of electronic parts inside of the housingpackage.

FIG. 3 is a front edge plan view of the device illustrated in FIG. 2showing positioning of the voice transducer device.

FIG. 4 is an exploded perspective view of the details of the voicetransducer device.

FIG. 5 is a schematic diagram of the electronic circuit employed toproduce the drive signal that actuates the transducer device.

FIG. 6 is a graphical waveform analysis of one of the possible preferredwaveforms attainable with the use of the device described herein.

In describing one selected form of preferred embodiment as shown in theDrawings and described in this specification, specific terms andcomponents are used for clarity. However, it is not intended to limitthe claimed Invention to the specific form, components or constructionshown and it is to be understood that the specific terms used in thisillustration of the Invention are intended to include all technicalequivalents which operate in a similar manner to accomplish a similarpurpose.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT OF INVENTION The specificembodiment of an improved unitary hand held multivibrator activatedartificial voice box sound source selected for purposes for illustrationherein consists generally of a compact housing structure, an astable,solid state, free running multivibrator, signal generator with provisionfor the variable symmetry output signal together with vibrator relaycoupling of said variable symmetry output waveform to an appropriateelectromechanical acoustic transducer with associated power supply andcontrol devices.

- An object of the improved device contemplated by this Invention beingto create a miniature hand held voice box for intermittent use that maybe used as simply and as easily as placing a cigarette in the user'smouth as illustrated in FIG. 1 of the Drawings herein, the device hasbeen fabricated to fit into a plastic package or housing 11approximately a size slightly smaller than the dimensions of a king sizecigarrette package. Like a cigarette package said electronic packagehousing 11 has a width greater than the thickness dimension of thepackage and has a height or length greater than the width of saidpackage. Miniature electronic transducer unit 12 is mounted on the upperend of housing package 11 on one of the minimum dimension edge surfaceswhile the push-to-talk off-on switch means 13 is mounted on one of thebroader width sides of electronic housing package 11 so that the thumbof the users hand holding the package may be employed to actuate saidpush-to-talk off-on switch means 13. FIG. 1 illustrates said housingpackage arranged for a left handed person but it will be readilyunderstood that a reversal of positioning of either the switch or thetransducer to an opposite surface will adapt the device to convenientone handed usage by right handed persons. The remaining features ofelectronics housing package 1 1 are conventional and may be readilydeduced or understood by examination of FIGS. 1 through 3 of theDrawings herein. The improved voice box apparatus proposed hereincontemplates the production of a loud, clear and readily modulatabletone signal of improved intelligibility by producing a variable symmetrygenerally rectangular waveform rich in harmonics. This is accomplishedby a combination of features and specially selected components includinga variable symmetry astable solid state multivib'rator circuit, to bediscussed later, employment of an electromagnetically actuated singlepole vibrating reed switch 14 employed both as an electromechanicalcoupling device and as a high contrast driving device for delivering anew high amplitude output signal to a selective electromechanicalacoustic transducer unit 12. The internal electromagnetic driver unit 15including a voice coil 15 and diaphragm 16 of miniature transducer unit12 are specially selected commercial driver elements capable of handlinga high voltage acoustic output. Rear casing unit 17 is of standardcommercial manufacture although the upper cover of transducer unit 12has been specially fabricated with surface mounting ears and an axiallypositioned external coupling throat projection 18 which serves as ameans of mounting flexible injection tube 19 as illustrated in detail inFIG. 4 of the Drawings herein.

The output signal from transducer unit 12 is acoustically coupled intothe-oral cavity of the user by means of a flexible plastic injector tube19 which is friction fitted onto throat structure 18 provided on theexternal cover of transducer unit 12. The employment of a flexiblecoupling or injector tube protects the user against accidental injury bysudden forceful collision between injector tube 19 and the lips or teethof the users mouth and also permits the user to lower said voice boxpackage 11 out of direct view of the users face while using theinstrument. It should be readily apparent from examination of FIG. 1 ofthe Drawings herein that the device as designed and fabricated lendsitself to manual intermittent use only at those moments when the useractually wishes to speak and that it can be readily removed or laidaside when the user is not speaking or when the'user is engaged in otheractivity.

Returning to an analysis of the solid state signal generator selectedfor this embodiment of the Invention, all of the electronicallyactuatable parts are wired in parallel with or across built in primarybattery energizer 20 which is in turn in series with push-to-talk offonswitch 13 which permits the user to employ the device intermittently atwill. Transistor 21 and transistor 22 are wired into a substantiallyconventional free running multivibrator circuit with the pulse output oftransistor 21 cross coupled by means of coupling capacitor 23 into theinput of transistor 22. Conversely the pulse output signal fromtransistor 22 is cross coupled by means of coupling capacitor 24 backinto the base input of transistor 21 such that each of said transistorpulse circuits consecutively drive first one then the other of said twopulse circuits into cut off so that transistor 21 is conducting whentransistor 22 is cut off or alternately transistor 22 is conducting whentransistor 21 is cut off in the familiar pattern for free runningmultivibrator circuits. The output pulse width for one half of theoutput waveform is determined by the discharge time constant of couplingcapacitor 23 through resistor 25 whereas the pulse width of thealternate side of the rectangular output waveforms is determined by thedischarged time constant of coupling capacitor 24 through resistor 26.

The output pulse from transistor circuit 22 has been made asymmetricalor longer than the output from transistor circuit 21 by adding to thecapacitance of coupling capacitor 24 the additional capacitance ofcapacitor 27 which for all effective purposes is wired in parallel withcoupling capacitor 24 so that the combined capacitance of capacitor 24plus capacitor 27 together lengthen the time constant for the dischargeof capacitor 24 through resistor 26 and this increment of increasedpulse-width caused by the parallel connection of capacitor 27 has beenmade variable by'pulse width control rheostat 28 so that the timeconstant for dischargingcapacitor 27 through .variable resistor 28 maybe adjusted to the convenience and preferences of the user of thedevice. 7

The output pulse from the collector of transistor 22 is routed throughthe input solenoid coil 29 of vibrating reed switch 14 so that solenoidcoil 29 serves as a load circuit for transistor 22 and also actuatesvibrating reed contactor 30 to vibrate in accordance with the frequencyand the pulse-width of the signals received from the output oftransistor 22. The switched side of vibrator switch 14 is wired inseries with a driver battery energizer 31 and the voice coil 15' ofelectromechanical transducer unit 12 so that the diaphragm of transducer12 is driven by DC pulses from battery energizer 31 as the DC circuitthrough vibrating reed switch 14 is opened and closed by the alternatingvibrations of vibrating reed contactor 30 in accordance with thefrequency and the pulse-width of the signals received from thepreviously described multivibrator signal generating circuit. It shouldbe noted that vibrating reed switch 14 is employed as a coupling devicefor transfer of the signal developed by the free running multivibratorsignal generator to transducer unit 12 and also serves as a mechanicalrepeater releasing a larger supply of DC energy from driver batterenergizer 31 at a frequency and pulse-width rate controlled by themultivibrator signal applied to input solenoid 29. FIG. 6 of theDrawings herein provides an oscilloscope graphic waveform analysis ofthe electrical output signal presented to transducer 12. During thelonger positive half cycle the pulse-width is affirmatively driven bycurrent flow from driver energizer battery 31 with several overshoots onthe first part of the leading half cycle. During the shorter negativehalf cycle it will be observed that diaphragm 16 of transreed switch 14is held open by the signal from said free running multivibrating signalgenerator. Also note that at the beginning of the negative half cyclethat there is a radical overshoot which may represent a feedbackreaction from the voice coil 15' of transducer 12. In any event thecombination of components described produces an anti symmetricalwaveform with a steeply rising leading edge and a rapidly fallingtrailing edge with a rich supply of harmonics at the beginning of eachpositive pulse. By employing a vibrating reed switch 14 repeater toprovide both coupling and additional signal drive, the Inventor has beenable to develope a high contrast or high amplitude asymmetricalrectangular waveform with a large and useful harmonic content that makesfor a more natural carrier tone signal and by providing for a convenientmeans of supplying intermittent signal tone when needed by depressing aconveniently situated thumb operated push-to-talk switch in the circuitthe proposed structure has made it possible to disable or silence thecarrying tone during the intermittent pause between words and sentencesand when the user is not speaking.

Returning to the physical arrangement of the components within theelectronics housing package ll. The lower parts of the interior of saidhousing structure 11 is occupied by insertable removable replaceableenergizer batteries 20 and 31 as illustrated in FIG. 2 of the Drawings.Most of the electronic components are mounted on a small aluminumchassis 32 or upon an electronic printed circuit board 33 as illustratedin FIG. 2 of the Drawings. Vibrating reed switch 14 is mounted in onecorner of aluminum chassis 32. However, note that the specificarrangement of components as illustrated in FIG. 2 and in FIG. 3 of theDrawings is not mandatory or critical and the exact physical placementof pulse-width control rheostat 28 has not been indicated. The exactpositioning of most of the physical components including the positioningof said pulsewidth control rheostat is a mechanical matter within thedisgression of a manufacturer or fabricator and a volume control couldlikewise be provided without departing from the spirit or purpose of theInvention.

OPERATION In normal operation the person desiring to use said electronicvoice box holds the device in one hand as illustrated in FIG. 1 of theDrawings and raises said voice box until it is directly in front of thelower part of the user's face at which time he inserts sound injectortube 19 into his mouth and simultaneously employs his thumb to depresspush-to-talk off-on switch 13 which causes the free runningmultivibrator signal generator to go into oscillation thereby producingthe rectangular wave shape signal previously described. Saidasymmetrical output signal is converted from electrical form into anacoustic signal in transducer 12 and is coupled into the mouth of theuser by means of flexible injection tube 19. The user then employs hislips and his tongue to modulate said flow of electronically producedsound to form words and communication sounds in much the same way thatwe use our lips and tongues to formulate words from the tones producedby our vocal chords. In the pauses between sentences or while waitingfor other persons to speak the user can disable and silence the devicesimply by releasing his or her thumb from the press-to-talk off-onswitch. The application and mastery of the use of the device is sosimple that most users should be able to teach themselves to operate thedevice by trial and error efforts within less than an hour afteracquiring possession of the device.

ADVANTAGES A material advantage of the Invention is that it provides ahighly compact, portable and self-contained electronic voice box sourceof speech modulatable sound that can be conveniently held andmanipulated in one hand in such manner as to leave the other hand freefor writing, holding a telephone or performing other tasks.

Another advantage of the Invention is that it provides an improvedartificial voice box apparatus provided with a conveniently positionedpush-to-talk switch means for intermittent operation thereby allowingthe patient or user to conveniently interrupt the sound source duringpauses in the speech pattern and during periods when other people arespeaking so that this particular device does not produce an annoyingbackground tone or noise during periods of nonuse.

Still a further advantage of this Invention is that the combination ofselected design and components and the employment of a vibrating reedswitch as a portion of the driver-repeater stage of the device producesan artificial voice source for laryngectomy patients that provides asubstantially increased volume or loudness that is better suited toproduce the frequency andcharacter of sounds that may be transmittedintelligibly over the telephone.

A still further advantage of the Invention is that it provides a compactmultivibrator electronic means of activating an improved sound generatorcapable of producing an asymetrical complex waveform rich in harmoniesto provide a more audible, more readily modulatable and more naturalsound for persons using the device.

Although this Specification describes but a single embodiment of theInvention with certain applications thereof, it should be understoodthat structural or material rearrangements or adequate or equivalentparts, substitutions of equivalent functional elements and othermodifications in structure can be made and other applications devisedwithout departing from the spirit and scope of my Invention. I thereforedesire that the description and drawings herein be regarded only as anillustration of my Invention and that the Invention be regarded aslimited only as set forth in the following claims, or as required by theprior art.

Having thus described my invention, I claim: 1. An improved unitary headheld multivibrator activated artificial voice box sound sourcecomprising:

A. an electronics package housing approximately the size of a king sizecigarette package; B. a transistorized, anti-symmetrical, free runningmultivibrator signal generating circuit; C. a built in battery powersupply to energize said transistorized multivibrator circuit; D. a pushto talk, off on switch means 1. wired in series with said battery powersupply,

and 2. located on one of the upper side panels of said housing packagewhere it can conveniently be reached for intermittent operation by thethumb of the operators hand holding the device;

7 8 E. a miniature electromagnetic acoustic transducer being wired inseries with the load circuit of one unit connected to the output of onehalf of said f th l i ib t transistors, d

multivibrator circuit with said transducer I. mounted in a surface mounthousing on the upper forward edge panel of said electronic housingpackage, and

2. the switched side of said vibrator switch being wired in series witha battery energizer and in series with the voice coil of said miniaturetrans- 2. being provided with an axially positioned output ducerf throatStructure; G. a flexible in ector tube connected to the trans- F. anelectromagnetically actuated single pole vibratducal throat structureand adapted to transmit the ing reed switch with 10 audio signal intothe mouth of the user. 1. the solenoid coil of said vibrating reedswitch

1. An improved unitary head held multivibrator activated artificialvoice box sound source comprising: A. an electronics package housingapproximately the size of a king size cigarette package; B. atransistorized, anti-symmetrical, free - running multivibrator signalgenerating circuit; C. a built in battery power supply to energize saidtransistorized multivibrator circuit; D. a push - to - talk, off - onswitch means
 1. wired in series with said battery power supply, and 2.located on one of the upper side panels of said housing package where itcan conveniently be reached for intermittent operation by the thumb ofthe operator''s hand holding the device; E. a miniature electromagneticacoustic transducer unit connected to the output of one half of saidmultivibrator circuit with said transducer
 1. mounted in a surface mounthousing on the upper forward edge panel of said electronic housingpackage, and
 2. being provided with an axially positioned output throatstructure; F. an electromagnetically actuated single pole vibrating reedswitch with
 1. the solenoid coil of said vibrating reed switch beingwired in series with the load circuit of one of the multivibratortransistors, and
 2. the switched side of said vibrator switch beingwired in series with a battery energizer and in series with the voicecoil of said miniature transducer; and G. a flexible injector tubeconnected to the transducer throat structure and adapted to transmit theaudio signal into the mouth of the user.
 2. the switched side of saidvibrator switch being wired in series with a battery energizer and inseries with the voice coil of said miniature transducer; and G. aflexible injector tube connected to the transducer throat structure andadapted to transmit the audio signal into the mouth of the user. 2.located on one of the upper side panels of said housing package where itcan conveniently be reached for intermittent operation by the thumb ofthe operator''s hand holding the device; E. a miniature electromagneticacoustic transducer unit connected to the output of one half of saidmultivibrator circuit with said transducer
 2. being provided with anaxially positioned output throat structure; F. an electromagneticallyactuated single pole vibrating reed switch with